Gauges: temp gauge question

[jocko]

I have an aftermarket temp gauge installed below the dash - a PO's answer to a defective in-dash factory gauge... Anyhoo - I've got a factory one that I'll install, but am curious if anyone might know if aftermarket senders are "universal." I don't actually know if the PO also changed over to the aftermarket mfgr's sender when the gauge was added or if he retained the original, or what was actually wrong with the original combo. While I'm sure a factory gauge "might" work with an aftermarket sender (i.e. a sender for an aftermarket, non-OEM gauge), I have no way of knowing if it's actually accurate. I have no problem swapping over the sender too, but just wondering if it is really necessary. I still have to dig into this a bit, and will just change the sender if there's any question, but just curious. Thanks!